JPH0874597A - Chain cover device of internal combustion engine - Google Patents

Abstract

PURPOSE: To prevent any aeration from occurring by installing an oil scattering preventing wall, preventing the scattering of lubricating oil in a chain cover, and an oil passage forming wall, collecting the lubricating oil and conducting it to a lubrication requiring part, both in this chain cover respectively. CONSTITUTION: Both first and second tensioner area P1 and P2 are installed on an inner surface of a chain cover 44, and the first tensioner area P1 is opened of its lower part alone and surrounded by three first tensioner side oil scattering preventive walls 48-1 to 49-3. Likewise, the second tensioner area P2 is opened of its lower part alone and surrounded by three second tensioner side oil scattering preventive walls 50-1 to 50-3. In addition, they are surrounded by those of first to ninth passage forming walls 54, 58, 64, 68, 76, 82, 86, 94 and 98 forming first to ninth oil passages 52, 56, 62, 66, 74, 80, 84, 92 and 96. With this constitution, such a possibility that lubricating oil might be scattered and thereby aeration is produced is thus preventable, so lubricating performance is well improvable in this way.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chain cover device for an internal combustion engine, and more particularly to improving lubrication performance,
The present invention relates to a chain cover device for an internal combustion engine that does not require a special oil supply device and can reduce noise generation.

[0002]

2. Description of the Related Art An internal combustion engine is provided with a chain such as a timing chain for transmitting the rotation of a crankshaft to another shaft, for example, a camshaft. This chain is wound around a crank sprocket of a crank shaft and a cam sprocket of a cam shaft, and its central portion is held at a predetermined tension by a chain tensioner or the like.

That is, as shown in FIG. 3, the internal combustion engine 202 comprises a cylinder block 204 and a cylinder head (not shown), and a crankshaft 206 is rotatably supported by the cylinder block 204. A crank sprocket 208 and a crank pulley 210 are attached to the end portion of the with a mounting bolt 212.
An intermediate shaft 214 is attached to the cylinder block 204 above the crank sprocket 208. The intermediate shaft 214 has a first intermediate sprocket 216 and a second intermediate sprocket 216.
An intermediate sprocket 218 is attached. A first chain 220 is wound around the crank sprocket 208 and the first intermediate sprocket 216. This first
The chain 220 is held at a predetermined tension by a first chain tensioner 222 protruding from the cylinder block 204. The second intermediate sprocket 218 has a second
The chain 224 is wrapped around. The second chain 224 is wound around a cam sprocket (not shown) of the cam shaft. This second chain 224 is
It is held at a predetermined tension by a second chain tensioner 226 protruding from the cylinder block 204.

A block side oil passage 228 is formed in the cylinder block 204. In the block side oil passage 228, a first branched oil passage 232 in which the first oil jet 230 on the first chain tensioner 222 side is formed and a second branched oil passage 232 on the second chain tensioner 226 side.
Second branched oil passage 2 in which oil jet 234 is formed
36 is in communication. In addition, the block side oil passage 2
28 includes a cylinder block 204 near the intermediate shaft 214.
The third branched oil passage 240 formed in the intermediate protruding portion 238 that is provided to communicate with each other is communicated. This third branch oil passage 240
On the tip side of the first and second intermediate sprockets 216, 2
Third oil jets 242-1 and 24 directed to the 18th side
2-2 are in communication.

As shown in FIGS. 3 and 4, the cylinder block 204 and the cylinder head include first and second chains 22.
The chain cover 244 and the cylinder head cover 246 are attached so as to cover 0 and 224, respectively.

As shown in FIG. 4, on the inner surface of the chain cover 244, there are crank sprocket locus CP, first and second
The intermediate sprocket locus MP, the first tensioner area P1, and the second tensioner area P2 are extracted.

In the chain cover device shown in FIGS. 3 and 4, the relief oil (lubricating oil) from the first and second oil jets 230 and 234 freely falls along the inner surface of the chain cover 244.

Further, such a chain cover device is disclosed in Japanese Utility Model Publication No. 62-15115 and Japanese Patent Laid-Open No. 3-91.
No. 4 and Japanese Utility Model Laid-Open No. 56-39807. The one described in Japanese Utility Model Publication No. 62-15115 is
The chain oil guide is placed below the sprocket cover that covers the chain drive sprocket, and one end of the chain oil guide is positioned behind the crossing portion of the exhaust pipe that traverses below the engine. This prevents the chain oil from smoking and causing smoke and ignition. Japanese Unexamined Patent Publication No. 3-914 discloses a blow-by gas in one of the spaces formed on the opposite side of the chain sliding side of two chain chains that press opposite parts of a timing chain in a direction in which they approach each other. An inlet is formed, an oil separator is arranged on the other side, and a communication passage for communicating the blow-by gas inlet and the oil separator by bypassing the chain installation space is arranged. Actual Kaisho 56-3
In the Japanese Patent Publication No. 9807, a cylinder-shaped oil jet pipe with a bottom is connected from the front surface of a cylinder block in the middle of a lubricating oil passage, and the oil jet pipe has a circumferential surface and a plurality of lubrication points of a timing chain, respectively. A plurality of oil outlets and holes are opened in an oriented manner.

[0009]

However, in the conventional chain cover device, the oil falls freely on the inner surface of the chain cover and the flow direction of the oil cannot be adjusted. Therefore, there is a disadvantage that air bubbles are dissolved in the oil due to the scattering of the air, so that so-called aeration occurs and the lubricating performance is deteriorated.

When driving the chain,
There is a disadvantage that a special oil supply device is required for a portion where oil supply is absolutely necessary, the structure is complicated, the weight is increased, and the cost is high.

[0011]

Therefore, in order to eliminate the above-mentioned inconveniences, the present invention provides a chain cover device for an internal combustion engine, in which a chain cover for covering a chain for transmitting the rotation of a crankshaft to another shaft is attached to the internal combustion engine. In the above, the chain cover is provided with an oil splash prevention wall for preventing scattering of the lubricating oil in the chain cover and a flow passage forming wall for an oil flow passage for collecting the lubricating oil and guiding it to a necessary lubrication portion. To do.

[0012]

According to the structure of the present invention, the lubricating oil in the chain cover does not scatter by the oil scattering prevention wall, and this lubricating oil is collected and guided to the lubrication necessary portion by the oil passage. This prevents the lubricating oil from scattering and causing so-called aeration, improving the lubricating performance, and eliminating the need for a special oil supply device, simplifying the structure, reducing the weight, and reducing the price, and It is possible to improve the rigidity of the chain cover itself and reduce the generation of noise.

[0013]

Embodiments of the present invention will be described in detail and specifically with reference to the drawings. 1 and 2 show an embodiment of the present invention. In FIG. 2, reference numeral 2 is an internal combustion engine. The internal combustion engine 2 includes a cylinder block 4 and a cylinder head (not shown).

A crankshaft 6 is supported by the cylinder block 4. A crank sprocket 8 and a crank pulley 10 are attached to the end portion of the crank shaft 6 with attachment bolts 12. An intermediate shaft 14 is attached to the cylinder block 4 above the crank sprocket 8. A first intermediate sprocket 16 and a second intermediate sprocket 18 are attached to the intermediate shaft 14. A first chain 20 is wound around the crank sprocket 8 and the first intermediate sprocket 16.
The first chain 20 is held at a predetermined tension by a first chain tensioner 22 protruding from the cylinder block 4. A second chain 24 is wound around the second intermediate sprocket 18. The second chain 24 is wound around a cam sprocket (not shown) of the cam shaft. The second chain 24 is held at a predetermined tension by a second chain tensioner 26 protruding from the cylinder block 4.

A block side oil passage 28 is formed in the cylinder block 4. In the block side oil passage 28, a first branched oil passage 32 in which a first oil jet 30 on the side of the first chain tensioner 22 is formed,
The second oil jet 3 on the side of the second chain tensioner 26
4 communicates with the second branched oil passage 36. Further, in the block side oil passage 28, the intermediate shaft 14
A third branched oil passage 40 formed in an intermediate protruding portion 38 protruding from the cylinder block 4 in the vicinity is in communication therewith. Two third oil jets 42-1 and 42-2 directed toward the first and second intermediate sprockets 16 and 18 are communicated with the tip end side of the third branched oil passage 40.

As shown in FIG. 1, a chain cover 44 and a cylinder head cover 46 are attached to the cylinder block 4 and the cylinder head so as to cover the first and second chains 20 and 24.

The inner surface of the chain cover 44 is shown in FIG.
As shown in, the crank sprocket locus MP, the first tensioner area P1, and the second tensioner area P2 are extracted.

Therefore, on the inner surface of the chain cover 44, an oil splash preventing wall for preventing the splash of relief oil (lubricating oil) in the first and second tensioner areas P1 and P2 and oil are collected to a lubrication necessary portion. A flow passage forming wall for guiding the oil flow passage is provided.

That is, the first tensioner region P1 is surrounded by the three first tensioner-side oil splattering prevention walls 48-1 to 48-3 so as to be open only below. Further, the second tensioner region P2 is surrounded by the three second tensioner-side oil splash prevention walls 50-1 to 50-3 so as to be open only below.

Below the second tensioner region P2, one end side of the first flow passage forming wall 54 forming the first oil flow passage 52 is arranged. The other end side of the first flow path forming wall 54 is inclined downward so as to surround the upper and one side of the intermediate sprocket locus MP along the rotation direction A of the first and second intermediate sprocket 16, 18. It is arranged in a curved shape. Above the first flow path forming wall 54, the second oil flow path 5 is inclined obliquely upward so as to intersect with the surface of the first flow path forming wall 54.
The second flow path forming wall 58 forming 6 is arranged linearly. Between the first flow path forming wall 54 and the second flow path forming wall 58,
The first flow gap 60 is formed.

The middle sprocket locus MC is surrounded by the upper end and one side by the other end of the first flow path forming wall 54, and the one side and lower half positions form the third oil flow path 62. It is surrounded by the curved third flow path forming wall 64, and the other side is surrounded by the one end side of the fourth flow path forming wall 68 forming the fourth oil flow path 66.
A second flow gap 70 is formed between the other end of the first flow path forming wall 54 and the second flow path forming wall 58. Further, the third flow path gap 7 is provided between the second flow path forming wall 58 and the third flow path forming wall 64.
2 is formed.

The second flow path forming wall 58 guides oil to the first and second intermediate sprockets 16 and 18 which are lubrication necessary parts. The third flow passage forming wall 64 also functions as a collecting wall that collects the oil supplied to the first and second intermediate sprockets 16 and 18.

The other end of the fourth flow path forming wall 68 is linearly extended obliquely downward. This fourth channel forming wall 6
Below the other end side of 8, the one end side of the fifth flow path forming wall 76 forming the fifth oil flow path 74 is disposed. The fourth flow gap 7 is provided between the fourth flow path forming wall 68 and the fifth flow path forming wall 76.
8 are formed. The other end side of the fifth flow path forming wall 76 is
It is disposed above the crank sprocket locus CP.

Below the first tensioner region P1, one end side of a sixth flow passage forming wall 82 forming the sixth oil flow passage 80 is arranged. The other end side of the sixth flow path forming wall 82 is inclined downward and is arranged in a curved shape in the rotation direction of the crank sprocket 8 so as to surround the upper side and one side of the crank sprocket locus CP. Above the sixth flow path forming wall 82, a seventh flow path forming which inclines obliquely upward so as to intersect the surface of the sixth flow path forming wall 82 and forms a seventh oil flow path 84. The wall 86 is linearly arranged. The fifth flow gap 8 is provided between the sixth flow path forming wall 82 and the seventh flow path forming wall 86.
8 are formed. Further, a sixth flow gap 90 is formed between the fifth flow path forming wall 76 and the sixth flow path forming wall 82.

The upper and one side of the crank sprocket locus CP is surrounded by the other end of the sixth flow passage forming wall 82, and the one side and the lower half position form the eighth oil flow passage 92. It is surrounded by the eighth flow passage forming wall 94, and the other side is surrounded by one end side of the ninth flow passage forming wall 98 forming the ninth oil flow passage 96. Between the other end side of the sixth flow path forming wall 82 and the eighth flow path forming wall 94, the seventh flow path is formed.
A gap 100 is formed. An eighth gap 102 is formed between the other end of the eighth flow passage forming wall 94 and one end of the ninth flow passage forming wall 98.

The sixth flow passage forming wall 82 guides oil to the crank sprocket 8 which is a lubrication necessary portion. The eighth flow passage forming wall 94 also functions as a collecting wall that collects the oil supplied to the crank sprocket 8. Further, the ninth flow path forming wall 98 guides oil to an oil pan (not shown).

Next, the operation of this embodiment will be described.

The relief oil from the second tensioner region P2 is scattered on the second tensioner side preventing walls 50-1 to 50-3.
The scattering is prevented by the sprocket, and the sprocket drops downward from the first oil flow path 52.
To the sixth oil flow path 8 through the third oil flow path 62, the fourth oil flow path 66, and the fifth oil 74.
It reaches 0. In addition, the relief oil from the first tensioner area P1 is scattered by the first tensioner side scattering prevention walls 48-1 to 48.
-3 prevents its scattering and falls downward,
It is guided by the oil flow path 80.

The oil in the sixth oil passage 80 is supplied to the crank sprocket 8, and then returned to the oil pan through the eighth oil passage 92 and the ninth oil passage 96.

As a result, the first and second tensioner areas P1,
Relief oil from P2 does not scatter,
Since this oil lubricates the lubrication required portion and is guided to the oil pan, it is possible to prevent the occurrence of so-called oil aeration due to the scattering of the oil and improve the lubrication performance.

Further, there is no need for a special oil supply device for supplying oil to the lubrication necessary parts such as the crank sprocket 8 and the like.
As a result, the structure can be simplified, the weight can be reduced, and the cost can be reduced.

Furthermore, since the oil splash prevention walls and the flow path forming walls described above are integrally attached to the chain cover 44,
The rigidity of the chain cover 44 itself is improved, so that
Vibration can be suppressed and the generation of noise can be reduced.

In this embodiment, the fourth oil passage 66 can be directly connected to the oil pan.

[0034]

As is apparent from the above detailed description, according to the present invention, the oil splash prevention wall for preventing the scattering of the lubricating oil in the chain cover and the oil passage for collecting the lubricating oil and guiding it to the lubrication necessary portion. By providing the flow path forming wall and the chain cover on the chain cover, it is possible to prevent the lubricating oil from scattering and causing so-called aeration to improve the lubricating performance.
A special oil supply device is not required, the structure is simple, the weight is reduced, the cost is low, and the rigidity of the chain cover itself is improved, so that noise generation can be reduced.

[Brief description of drawings]

FIG. 1 is a front view of the inside of a chain cover.

FIG. 2 is a cross-sectional view of a chain cover portion of the internal combustion engine with a chain cover removed.

FIG. 3 is a cross-sectional view of a chain cover portion to which a chain cover of a conventional internal combustion engine is attached.

FIG. 4 is a front view of the inside of a conventional chain cover.

[Explanation of symbols]

 2 Internal combustion engine 4 Cylinder block 8 Crank sprocket 16 First intermediate sprocket 18 Second intermediate sprocket 20 First chain 24 Second chain 44 Chain cover 48 First tensioner-side anti-scattering wall 50 Second tensioner-side anti-scattering wall 52 First oil Flow path 56 2nd oil flow path 62 3rd oil flow path 66 4th oil flow path 74 5th oil flow path 80 6th oil flow path 84 7th oil flow path 92 8th oil flow path 96 9th oil flow path

[Procedure amendment]

[Submission date] November 7, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

FIG.

[Fig. 2]

[Figure 3]

[Figure 4]

Claims (1)

[Claims] 1. A chain cover device for an internal combustion engine in which a chain cover for covering a chain for transmitting rotation of a crankshaft to another shaft is attached to an internal combustion engine, and an oil splash prevention wall for preventing splash of lubricating oil in the chain cover. A chain cover device for an internal combustion engine, wherein the chain cover is provided with a flow path forming wall of an oil flow path that collects lubricating oil and guides it to a lubrication necessary portion.